This invention relates to the production of thermoplastic tubing and, more particularly, relates to a method and apparatus for producing small and large diameter thermoplastic tubing and composite tubular structures.
U.S. Pat. No. 4,911,633 issued March 27, 1990 discloses an apparatus for producing plastic tubing in which a plurality of mold carriages each supporting a pair of clam shell mold blocks is mounted in a framework for reciprocal linear travel. First actuating means are employed for moving the carriages to an extrusion station, second actuating means are employed for opening and closing the clam shell mold blocks carried by the carriages, and third actuating means are employed for returning the carriages rearwardly to a start position.
It is a principal object of the present invention to provide a single actuating means for moving the carriages and associated mold blocks in a reciprocal linear path to and from an extrusion station, thereby simplifying construction and operation of the apparatus.
It is another object of the present invention to provide an improved actuating means for closing and opening the mold blocks prior to and after molding of plastic tubing and composite tubular structures therein.